Surgery-induced peritoneal cancer cells in patients who have undergone curative gastrectomy for gastric cancer

Five-year survival outcome of laparoscopic D2 lymphadenectomy plus complete mesogastrium excision for patients with stage II/III gastric cancer without invasion of the squamocolumnar junction

BACKGROUND

Gastric cancer patients without invasion of the squamocolumnar junction have a low probability of extragastric mesenteric metastasis, and the survival benefit of conducting D2 lymphadenectomy plus complete mesogastrium excision is unclear in this group of patients.

METHODS

This was a retrospective analysis of patients with stage II/III gastric cancer without invasion of the squamocolumnar junction who underwent laparoscopic radical surgery for gastric cancer at the First Hospital of Putian City, Fujian Province, from January 2014 to May 2019. Five-year disease-free survival was the primary outcome, and 5-year overall survival and the recurrence pattern were the secondary outcomes. Morbidity, mortality, and surgery-related outcomes within 30 days of surgery were also analyzed.

RESULTS

This study included 366 patients, 133 in the D2 lymphadenectomy group and 233 in the D2 lymphadenectomy plus complete mesogastrium excision group. There was no statistically significant difference in 5-year disease-free survival and overall survival in the D2 lymphadenectomy plus complete mesogastrium excision group compared with the D2 lymphadenectomy group (P > .05). Regarding recurrence pattern, the D2 lymphadenectomy group had a higher rate of local recurrence (12.3% and 38.3%, P = .001). In subgroup analysis, patients with stage III and T3-4aN1-3 gastric cancer in the D2 lymphadenectomy plus complete mesogastrium excision group had significantly better 5-year disease-free survival compared with the D2 lymphadenectomy group (P < .05).

CONCLUSION

Laparoscopic D2 lymphadenectomy plus complete mesogastrium excision not only decreased the local recurrence rate of stage II/III gastric cancer without invasion of the squamocolumnar junction, but it also improved the 5-year disease-free survival of patients with stage III and T3-4aN1-3 gastric cancer without invasion of the squamocolumnar junction.

A comprehensive overview of gastric cancer management from a surgical point of view

Despite advancements in medical care, surgical technologies, and the development of novel treatments over the past decade, the prognosis for patients with gastric cancer (GC) has only modestly improved. This is primarily due to the fact that the majority of patients are diagnosed at advanced stages or present with metastatic disease. Radical resection remains the cornerstone of potentially curative treatment, yet the overall 5-year survival rate remains below 35%. The management of GC varies globally, influenced by factors such as geographical disparities, patient comorbidities and performance status, surgical approaches, and available medical resources. Multidisciplinary collaboration and a multimodal treatment approach are essential for optimizing patient outcomes. Surgeons must stay updated on emerging surgical concepts and make informed decisions regarding patient selection, timing of intervention, and the adoption of appropriate surgical techniques to improve both quality of life and prognosis. This review aims to provide a surgical perspective on the management of GC across all stages, highlighting the importance of a comprehensive treatment approach. Endoscopic resection may be a viable option for early GC in patients with minimal risk of lymph node metastasis, particularly in elderly patients with high surgical risk or severe comorbidities. For advanced GC, neoadjuvant therapy followed by surgery could be a promising strategy to improve patient outcomes. Conversion surgery offers a potential survival benefit for patients who respond to treatment with tumor downstaging. The treatment of peritoneal carcinomatosis remains challenging; however, hyperthermic intraperitoneal chemotherapy combined with complete cytoreductive surgery or pressurized intraperitoneal aerosolized chemotherapy may prolong survival or improve quality of life in highly selected patients.

Top Peritoneal Surface Malignancy Articles from 2022 to Inform your Cancer Practice

Over the last few decades, the role of cytoreductive surgery (CRS) with or without regional-based peritoneal therapies such as hyperthermic intraperitoneal chemotherapy (HIPEC) has evolved in the management of patients with peritoneal surface malignances (PSMs). Despite the benefit of CRS in improving oncologic outcomes, significant challenges remain in the treatment of patients with advanced PSMs, and the role of HIPEC continues to be questioned. Additionally, while there has been improvement in perioperative outcomes, long-term survival remains poor. As a result, there is much need to improve our understanding of the processes that drive tumor biology, thereby improving patient selection for various treatment approaches. Additionally, newer therapies are needed for patients who remain poor surgical candidates and who progress on systemic therapy. This article highlights recently published studies that we consider impactful in the care of patients with PSMs.

Indocyanine green fluorescence imaging-guided versus conventional laparoscopic lymphadenectomy for gastric cancer: long-term outcomes of a phase 3 randomised clinical trial

Indocyanine green (ICG) fluorescence imaging-guided lymphadenectomy has been demonstrated to be effective in increasing the number of lymph nodes (LNs) retrieved in laparoscopic gastrectomy for gastric cancer (GC). Previously, we reported the primary outcomes and short-term secondary outcomes of a phase 3, open-label, randomized clinical trial (NCT03050879) investigating the use of ICG for image-guided lymphadenectomy in patients with potentially resectable GC. Patients were randomly (1:1 ratio) assigned to either the ICG or non-ICG group. The primary outcome was the number of LNs retrieved and has been reported. Here, we report the primary outcome and long-term secondary outcomes including three-year overall survival (OS), three-year disease-free survival (DFS), and recurrence patterns. The per-protocol analysis set population is used for all analyses (258 patients, ICG [n = 129] vs. non-ICG group [n = 129]). The mean total LNs retrieved in the ICG group significantly exceeds that in the non-ICG group (50.5 ± 15.9 vs 42.0 ± 10.3, P < 0.001). Both OS and DFS in the ICG group are significantly better than that in the non-ICG group (log-rank P = 0.015; log-rank P = 0.012, respectively). There is a difference in the overall recurrence rates between the ICG and non-ICG groups (17.8% vs 31.0%). Compared with conventional lymphadenectomy, ICG guided laparoscopic lymphadenectomy is safe and effective in prolonging survival among patients with resectable GC.

Efficacy of chemotherapy versus surgery as initial treatment for gastric cancer with positive peritoneal cytology

BACKGROUND

The prognosis of gastric cancer (GC) patients with positive peritoneal cytology (CY1) without other distant metastasis is poor, and there are no standard treatment strategies. Our study aimed to compare the survival outcomes of CY1 GC patients receiving chemotherapy or surgery as initial treatment.

METHODS

From February 2017 to January 2020, clinical and pathological data of patients diagnosed with CY1 GC without other distant metastasis in the Peking University Cancer Hospital was reviewed. Patients were divided into two groups: chemotherapy-initial group and surgery-initial group. In chemotherapy-initial group, patients received preoperative chemotherapy initially. According to the treatment response, the patients were divided into three subgroups: conversion gastrectomy group, palliative gastrectomy group, and further systematic chemotherapy group. In surgery-initial group, patients underwent gastrectomy followed by postoperative chemotherapy.

RESULTS

A total of 96 CY1 GC patients were included with 48 patients in each group. In chemotherapy-initial group, preoperative chemotherapy yielded an objective response rate of 20.8% and disease control rate of 87.5%. Conversion to CY0 after preoperative chemotherapy was obtained in 24 (50%) patients. The median overall survival was 36.1 months in chemotherapy-initial group and 29.7 months in surgery-initial group (p = 0.367). The median progression-free survival was 18.1 months in chemotherapy-initial group and 16.1 months in surgery-initial group (p = 0.861). The 3-year overall survival rates were 50.0% and 47.9%, respectively. In chemotherapy-initial group, twenty-four patients who converted to CY0 by preoperative chemotherapy and received surgery obtained a significantly better prognosis. The median overall survival was still not reached in these patients.

CONCLUSION

There was no significant difference in survival outcomes between chemotherapy-initial group and surgery-initial group. CY1 GC patients who converted to CY0 by preoperative chemotherapy and received radical surgery could obtain a favorable long-term prognosis. Further investigation should focus on preoperative chemotherapy to eliminate peritoneal cancer cell.

TRIAL REGISTRATION

This study is retrospectively registered.

Development of the Peritoneal Metastasis: A Review of Back-Grounds, Mechanisms, Treatments and Prospects

Peritoneal metastasis is a malignant disease which originated from several gastrointestinal and gynecological carcinomas and has been leading to a suffering condition in patients for decades. Currently, as people have gradually become more aware of the severity of peritoneal carcinomatosis, new molecular mechanisms for targeting and new treatments have been proposed. However, due to the uncertainty of influencing factors involved and a lack of a standardized procedure for this treatment, as well as a need for more clinical data for specific evaluation, more research is needed, both for preventing and treating. We aim to summarize backgrounds, mechanisms and treatments in this area and conclude limitations or new aspects for treatments.

The Role of Surgery in the Management of Gastric Cancer: State of the Art

Surgery still represents the mainstay of treatment of all stages of gastric cancer (GC). Surgical resections represent potentially curative options in the case of early GC with a low risk of node metastasis. Sentinel lymph node biopsy and indocyanine green fluorescence are novel techniques which may improve the employment of stomach-sparing procedures, ameliorating quality of life without compromising oncological radicality. Nonetheless, the diffusion of these techniques is limited in Western countries. Conversely, radical gastrectomy with extensive lymphadenectomy and multimodal treatment represents a valid option in the case of advanced GC. Differences between Eastern and Western recommendations still exist, and the optimal multimodal strategy is still a matter of investigation. Recent chemotherapy protocols have made surgery available for patients with oligometastatic disease. In this context, intraperitoneal administration of chemotherapy via HIPEC or PIPAC has emerged as an alternative weapon for patients with peritoneal carcinomatosis. In conclusion, the surgical management of GC is still evolving together with the multimodal strategy. It is mandatory for surgeons to be conscious of the current evolution of the surgical management of GC in the era of multidisciplinary and tailored medicine.

Gastric and gastroesophageal junction cancer: Risk factors and prophylactic treatments for prevention of peritoneal recurrence after curative intent surgery

Aim

Relapse after curative treatment for advanced gastric cancer, and especially peritoneal recurrence, is very common and has a dismal prognosis. The aim of this review is to summarize existing evidence regarding risk factors and prophylactic treatments intending to prevent peritoneal recurrence.

Methods

A structured search of relevant studies was conducted in MEDLINE, Embase, and the Cochrane Library.

Results

The main risk factors identified are advanced pathological T-stage (pT ≥ 3), regional lymph node involvement, diffuse/poorly cohesive type tumor, poorly differentiated cancer, and positive peritoneal wash cytology. Systemic chemotherapy in the perioperative or adjuvant setting improves survival for the patients but despite this peritoneal recurrence remains a common and yet an unsolved clinical problem. Different approaches of intraperitoneal chemotherapy such as hyperthermic intraperitoneal chemotherapy and early postoperative intraperitoneal chemotherapy have shown promising results as prophylactic treatments aiming to prevent peritoneal recurrence.

Conclusion

Future studies are warranted to find safe and effective treatments to prevent peritoneal recurrence.

Adverse impact of postoperative intra-abdominal infectious complications on cancer recurrence-related survival after curative gastric cancer surgery

BACKGROUND

This study aimed to evaluate the impact of postoperative intra-abdominal infectious complications (PICs) on survival after surgery for gastric cancer.

METHODS

A total of 152 patients who underwent curative gastrectomy for gastric cancer were included. The effect of clinicopathological features and PICs on recurrence-free survival (RFS) and overall survival (OS) were investigated.

RESULTS

The median age was 67 years. The pathological stage was stage I (61), II (40), and III (51). Thirty-two patients (21.1%) had PICs: 9, pancreatic fistula; 14, anastomotic leakage; and 17, intra-abdominal abscess. The five-year RFS and OS rates were significantly lower in patients with PICs than in those without PICs (63.4 vs. 85.6%; p < 0.01 and 56.4 vs. 80.3%; p < 0.01, respectively). In multivariate analysis, intraoperative blood loss was an independent prognostic factor for PICs.

CONCLUSIONS

Patients with PICs had worse clinical outcomes. Reducing intraoperative bleeding may improve the prognosis of gastric cancer.

Development of the PERI-Gastric (PEritoneal Recurrence Index) and PERI-Gram (Peritoneal Recurrence Index NomoGRAM) for predicting the risk of metachronous peritoneal carcinomatosis after gastrectomy with curative intent for gastric cancer

BACKGROUND

A model that quantifies the risk of peritoneal recurrence would be a useful tool for improving decision-making in patients undergoing curative-aim gastrectomy for gastric cancer (GC).

METHODS

Five Italian centers participated in this study. Two risk scores were created according to the two most widely used pathologic classifications of GC (the Lauren classification and the presence of signet-ring-cell features). The risk scores (the PERI-Gastric 1 and 2) were based on the results of multivariable logistic regressions and presented as nomograms (the PERI-Gram 1 and 2). Discrimination was assessed with the area under the curve (AUC) of receiver operating curves. Calibration graphs were constructed by plotting the actual versus the predicted rate of peritoneal recurrence. Internal validation was performed with a bootstrap resampling method (1000 iterations).

RESULTS

The models were developed based on a population of 645 patients (selected from 1580 patients treated from 1998 to 2018). In the PERI-Gastric 1, significant variables were linitis plastica, stump GC, pT3-4, pN2-3 and the Lauren diffuse histotype, while in the PERI-Gastric 2, significant variables were linitis plastica, stump GC, pT3-4, pN2-3 and the presence of signet-ring cells. The AUC was 0,828 (0.778-0.877) for the PERI-Gastric 1 and 0,805 (0.755-0.855) for the PERI-Gastric 2. After bootstrap resampling, the PERI-Gastric 1 had a mean AUC of 0.775 (0.721-0.830) and a 95%CI estimate for the calibration slope of 0.852-1.505 and the PERI-Gastric 2 a mean AUC of 0.749 (0.693-0.805) and a 95%CI estimate for the slope of 0.777-1.351. The models are available at www.perigastric.org .

CONCLUSIONS

We developed the PERI-Gastric and the PERI-Gram as instruments to determine the risk of peritoneal recurrence after curative-aim gastrectomy. These models could direct the administration of prophylactic intraperitoneal treatments.

Surgical Management of Gastric Cancer: A Review

Importance

Surgery plays a critical role in the management of all stages of gastric cancer.

Observations

For patients with early gastric cancer and low risk of lymph node metastasis, endoscopic therapy or surgery alone is potentially curative. Novel techniques, such as sentinel lymph node biopsy, may allow for greater use of stomach-sparing procedures that could improve quality of life without compromising oncologic outcomes; however, experience with these techniques is rare outside of East Asia, and studies of long-term outcomes are still ongoing. Patients with later-stage localized gastric cancer benefit from more extensive lymphadenectomy and multimodality therapy, as they are at risk for nodal and distant metastases. There have been recent advances in chemotherapy that have led to improved survival, but the optimal sequencing of multimodality therapy is still being investigated. Better systemic therapy may also increase the role of surgery for patients with oligometastatic disease. There are ongoing studies examining the efficacy of peritoneal-directed therapies in both patients with low-volume peritoneal disease and patients at high risk of peritoneal recurrence.

Conclusions and Relevance

The management of gastric cancer continues to evolve. Surgeons should be aware of novel surgical approaches currently under investigation as well as how surgery fits into the contemporary multidisciplinary approach to this disease.

Predictive Effect of Systemic Immune-Inflammation Index Combined With Prognostic Nutrition Index Score on Efficacy and Prognosis of Neoadjuvant Intraperitoneal and Systemic Paclitaxel Combined With Apatinib Conversion Therapy in Gastric Cancer Patients With Positive Peritoneal Lavage Cytology: A Prospective Study

Background

Gastric cancer with only peritoneal lavage cytology (GC-CY₁) is a special type of gastric cancer, which is defined as stage IV. The pre-treatment systemic immune-inflammation index (SII) and prognostic nutritional index (PNI) are representative blood indexes of systemic inflammatory response and nutritional status. However, the clinical significance of combined detection of these two indexes is still unclear. This study aims to evaluate the clinical value of the new score system by combining SII and PNI (SII-PNI score) as a predictor of efficacy and prognosis after neoadjuvant intraperitoneal and systemic (NIPS) paclitaxel combined with Apatinib conversion therapy for GC-CY₁ patients.

Methods

We registered a prospective clinical study involving 36 GC-CY₁ patients from April 2018 to August 2019 (NCT03718624). All patients underwent re-laparoscopic exploration after treatment. According to free cancer cells (FCCs) status, these patients were divided into FCCs group and non-FCCs group. The SII-PNI score ranged from 0 to 2 as follows: score of 2, high SII (≥512.1) and low PNI (≤52.9); score of 1, either high SII or low PNI; score of 0, no high SII nor low PNI.

Results

All patients underwent re-laparoscopic exploration after 3 cycles of NIPS paclitaxel and Apatinib conversion therapy. Among them, 28 cases (77.78%) were in non-FCCs group, and 8 cases (22.22%) were in FCCs group. The SII-PNI score of non-FCCs patients was significantly lower than that of FCCs patients (p=0.041). The prognosis of patients with high SII-PNI score was significantly worse than that of patients with low SII-PNI score (p<0.001). Multivariate analysis showed that SII-PNI score was an independent prognostic factor for predicting overall survival and progression-free survival (p=0.001, 0.002).

Conclusion

Pretreatment SII-PNI score is an important predictor for the efficacy of GC-CY₁ patients after NIPS paclitaxel combined with Apatinib conversion therapy, which can help to identify high-risk groups and predict prognosis.

Risk factors and oncological impact of positive resection margins in gastrectomy for cancer: are they salvaged by an additional resection?

BACKGROUND

The situation of positive resection margins (PRMs) varies notably between Western and Asian countries. In the West, PRMs are associated with advanced disease and R1, whereas in Asia, PRMs are also considered in early disease because stomach preservation was recently prioritized. Furthermore, PRMs are usually resected to obtain R0. However, the oncological impact of PRMs and additional resection remains unclear. The aim of this study is to evaluate the oncological impact of PRMs in laparoscopic gastrectomy (LG) for clinical stage (cStage) I gastric cancer.

METHODS

A total of 2121 patients who underwent LG for cStage I gastric cancer between 2007 and 2015 were enrolled. Survival outcomes were compared between patients with PRMs (group P) and those without (group N). Furthermore, prognostic factors were analyzed using multivariate analysis.

RESULTS

Twenty-seven patients (1.3%) had PRMs. Patients in group P had upper and more advanced disease, and the 5-year relapse-free survival (RFS) rate was worse in group P compared with group N (76.3% vs. 95.1%, P = 0.003). The 5-year RFS of patients with pT2 or deeper (pT2-4) disease in group P was significantly worse than that of patients in group N (66.7% vs. 89.5%, P = 0.030) although that of patients with pT1 was not. Likelihood ratio tests showed that there was a significant interaction between pT status and PRM (P = 0.005).

CONCLUSION

PRM in cStage I gastric cancer is associated with advanced upper disease. It remains an independent prognostic factor in pT2-4 disease even after an additional resection to obtain R0.

Safety and efficacy of water pressure endoscopic submucosal dissection for colorectal tumors with submucosal fibrosis (with video)

BACKGROUND AND AIMS

Colorectal neoplasms with submucosal fibrosis are the most challenging targets of endoscopic resection. Water pressure endoscopic submucosal dissection (WP-ESD) is a recently introduced procedure that has several advantages over conventional endoscopic submucosal dissection (C-ESD). This study aimed to assess the efficacy and safety of WP-ESD for fibrotic colorectal neoplasms.

METHODS

This retrospective observational study investigated 133 colorectal neoplasms expected to have submucosal fibrosis that were resected by WP-ESD or C-ESD between April 2012 and April 2020. Eighty-seven lesions after endoscopic or surgical treatment, 18 with biopsy scar with fold convergence and 28 in patients with ulcerative colitis, were included. The differences in treatment outcomes, including procedure time and adverse event proportions, between the WP-ESD and C-ESD groups were analyzed. The clinical course after perforation using WP-ESD was also evaluated, including postprocedural multidetector CT findings obtained immediately after WP-ESD.

RESULTS

Severe submucosal fibrosis was observed in 96 lesions (72.2%). The median procedure time was significantly shorter in the WP-ESD group than in the C-ESD group (43.5 minutes [interquartile range {IQR}, 32.8-73] vs 72 minutes [IQR, 45-105]; P = .0041). The multivariate analysis revealed WP-ESD as an independent factor for a short procedure time (odds ratio, 2.90; 95% confidence interval, 1.28-6.55). The proportions of post-ESD electrocoagulation syndrome (11.6% vs 13.1%) and perforation (20.4% vs 22.8%) were similar between the groups. Four of 11 patients with perforation who underwent WP-ESD showed fluid collection on postprocedural multidetector CT images.

CONCLUSIONS

WP-ESD can shorten procedure time for treating fibrotic colorectal neoplasms.

Long-term prognosis of patients with cancer-related genes detected in postoperative peritoneal washings obtained during curative gastrectomy

BACKGROUND

Cancer cells in intraoperative peritoneal washings (PW) indicate increased peritoneal recurrence. Detection of CEA or CK20 genes indicates poor prognosis. We assessed long-term prognosis of patients with amplification of cancer-related genes in PW obtained intraoperatively during curative gastric cancer surgery.

METHODS

PW was collected before and immediately after curative gastrectomy. CEA, CK20, TFF1, MUC2, and FABP1-mRNA were selected as marker genes for reverse transcription polymerase chain reaction. Peritoneal recurrence-free survival (PRFS) and overall survival (OS) after >7-year follow-up were examined using the Kaplan-Meier method.

RESULTS

Of 138 patients who underwent gastrectomy with negative cytological findings at laparotomy, 80 patients showed negative cancer-related gene amplification in preoperative PW. Fifty-eight patients were excluded due to positive gene amplification, which suggested presence of preoperative peritoneal cancer cells. The 80 patients had mRNA amplification in PW after surgery. Amplification of multiple and single cancer-related marker genes was observed in 38 and 21 patients; 21 cases had marker-negative results. Five-year PRFS was 69.1%, 95.2%, and 100% in multi-marker-positive, single marker-positive, and marker-negative cases, respectively. Multi-marker-positive patients had significantly worse PRFS than the other groups (p < 0.05). Multivariate analysis in the Cox proportional hazards model identified multi-marker-positivity as an independent prognostic factor for PRFS (hazard ratio, 7.6; 95% confidence interval, 1.07-62.63; p = 0.046), and multi-marker-positive patients had significantly worse OS than other groups (p < 0.01).

CONCLUSION

Multi-marker cancer-related gene amplification in PW is associated with worse prognosis in PRFS and OS even after a long follow-up; PRFS can be stratified by the number of genes amplified.

The Cell Line-Dependent Diversity in Initial Morphological Dynamics of Pancreatic Cancer Cell Peritoneal Metastasis Visualized by an Artificial Human Peritoneal Model

BACKGROUND

Pancreatic ductal adenocarcinoma is considered as one of the most malignant types of cancer with rapid metastasis and invasion of the cancer cells, having peritoneal metastasis (PM) as a dominant factor of poor prognosis. Although the prevention of peritoneal dissemination would result in the inhibition of the initial metastatic process and contribute in improving the poor prognosis of the pancreatic cancer, the initial dynamics of PM are still unclear because of the lack of adequate models in studying the morphological and molecular details of pancreatic cancer cells.

MATERIALS AND METHODS

The artificial human peritoneal tissue (AHPT) that can be applied in studying for the spatial dynamics of cancer PM in vitro has been established previously. In this study, the initial dynamics of the three pancreatic cell lines, undifferentiated carcinoma MIA PaCa-2, poorly differentiated adenocarcinoma Panc-1, and moderately differentiated adenocarcinoma BxPC3 on AHPT are examined.

RESULTS

In a morphological analysis using light and electron microscopy, MIA PaCa-2 cells spread on the mesothelial layer with disruption of the sheet structure and infiltrated into the stroma-like tissue in AHPT. On the other hand, BxPC3 cells changed shapes from round into flat ones with rapid proliferation and formed sheet structure at the surface of the tissue replacing the mesothelial layer without vertical invasion into the tissue. Panc-1 cells demonstrated the intermediate characteristics of MIA PaCa-2 and BxPC3 on AHPT. These diverse morphological characteristics were verified by the correspondence with the results in a mouse model and were reflected by the profile of secreted oncogenic proteins of the three pancreatic cell lines.

CONCLUSIONS

The initial dynamics in the peritoneal dissemination of these pancreatic cancer cell lines were demonstrated by AHPT, showing the morphological and molecular diversity depending on the degree of differentiation or the properties of oncogenic protein secretion.

Cytopathologic assessment of gloves and instruments after major head and neck surgery

PURPOSE

To investigate the potential for cancer cells to be transferred between anatomic sites via instruments and other materials.

MATERIALS AND METHODS

Pilot prospective study from April 2018-January 2019 at Rush University Medical Center. Glove and instrument washings were collected from 18 high-risk head and neck cancer resection cases (36 samples total). Each case maintained at least one of the following features in addition to a diagnosis of squamous cell carcinoma or sarcoma: palliative/salvage surgery, positive margins, extensive tumor burden, and/or extra capsular extension (ECE). Surgical gloves and four main instruments were placed through washings for blind cytological assessment (2 samples/case).

RESULTS

18 patients undergoing surgical tumor resection for biopsy-proven squamous cell carcinoma with at least one of the aforementioned characteristics were included. 26.7% of cases had ECE, 40.0% had positive final margins and 46.7% had close final margins. Tumor locations included: oral cavity (10), neck (4), parotid gland (2), and skin (2). Malignant cells were isolated on glove washings in 1 case (5.5%). No malignant cells were isolated from instrument washings. The single case of malignant cells on glove washings occurred in a recurrent, invasive squamous cell carcinoma of the scalp with intracranial extension. Anucleated squamous cells likely from surgeon skin were isolated from 94.4% of washings. Squamous cells were differentiated from mature cells by the absence of nuclei.

CONCLUSIONS

Malignant squamous cells can be isolated from surgical glove washings, supporting the practice of changing of gloves after gross tumor resection during major head and neck cancer resections.

Hyperthermic intraperitoneal chemotherapy in prevention of gastric cancer metachronous peritoneal metastases: a systematic review

Gastric cancer progression resulting in metachronous peritoneal metastasizing is almost always associated with an adverse prognosis. This review discusses various options of preventing metachronous peritoneal metastases in radically operated gastric cancer patients. Also examined are different hyperthermic intraperitoneal chemotherapy (HIPEC) regimens employed in gastric cancer treatment, postoperative morbidity and mortality rates and long-term treatment outcomes. The authors also review their own experience of using HIPEC based on the combination of cisplatin and doxorubicin in doses of 50 mg/m² at 42 °C for 1 h to prevent gastric cancer peritoneal dissemination. As a result, progression-free survival rose from 19.6%±5.6% to 47.1%±6.3% (P_log-rank <0.001) and dissemination-free survival-from 22.7%±6.0% to 51.9%±6.3% (P_log-rank <0.001). It is noted that the combination of the described HIPEC regimen with systemic chemotherapy helped raise metastases-free 3-year survival rate to up to 91.0%±9.0% (P_log-rank =0.025) compared with 48.6%±6.4% for patients who underwent only a combined surgery/HIPEC treatment. HIPEC is a promising combined treatment strategy for radically operated gastric cancer patients that can improve patient survival and decrease peritoneal dissemination rate. However, the number of randomized studies on adjuvant HIPEC are still insufficient for a subgroup assessment of efficacy of the given chemotherapy regimens and generation of evidence-based recommendations on the individual use of chemotherapy agents and their combinations, and HIPEC procedural techniques. Further prospective randomized studies are needed to assess the practicability of complementing HIPEC with adjuvant systemic chemotherapies.

Effects of Laparoscopic Radical Gastrectomy on Peritoneal Micrometastases of Gastric Cancer

BACKGROUND

Some reports asserted that the stimulation of ultrasonic scalpel and the persistent state of carbon dioxide (CO2) pneumoperitoneum in laparoscopic surgery may affect the adhesion and invasion of gastric cancer (GC) cells. This study aimed to reveal the effects of laparoscopic radical gastrectomy on peritoneal micrometastases (PM) of GC.

MATERIALS AND METHODS

Fifty-three patients who underwent laparoscopic radical gastrectomy for GC were enrolled in the study. The expressions of carcinoembryonic antigen (CEA) mRNA and dopa decarboxylase (DDC) mRNA in peritoneal lavage fluid were detected by reverse transcription-polymerase chain reaction. The positive rates of CEA mRNA and DDC mRNA in preoperative peritoneal lavage fluid (pre-CEA, pre-DDC) were compared with those in postoperative lavage fluid (post-CEA, post-DDC). The correlation between the expressions of pre-CEA and pre-DDC and clinicopathologic factors and disease-free survival was analyzed.

RESULTS

There was no significant difference in the positive rates of pre-CEA and pre-DDC compared with those of post-CEA and post-DDC (all P>0.05). The positive rates of pre-CEA and pre-DDC increased with the increase of TNM stage, deepening of invasion, lymph node metastasis, and serosal invasion (all P<0.05), but had no correlation with tumor location, size, degree of differentiation, nerve invasion, and vascular invasion (all P>0.05). The disease-free survival in the combined positive patients was lower than that in the negative patients.

CONCLUSIONS

Laparoscopic radical gastrectomy for GC is safe and feasible, without increasing the risk of PM. The PM of GC may be associated with late tumor stage, deep infiltration, lymph node metastasis, and serosal invasion.

Combination of tumor cell anti-adhesion and anti-tumor effect to prevent recurrence after cytoreductive surgery in a mice model

One of the main problems of colorectal cancer is not the treatment of the primary tumor but the metastatic stage. Means of metastatic spread is the invasion of the peritoneal cavity which leads to peritoneal metastasis (PM). PM cannot be easily cured, and the current treatments is rather heavy, combining cytoreductive surgery with intravenous and intraperitoneal chemotherapy. This therapeutic procedure is associated with significant morbidity, altered patient quality of life and poor prognosis. We postulated that development of a prophylactic treatment could be of high interest in this context. In this study, we formulated an anti-adhesive thermogel which contains chemotherapeutics to play a role of a barrier against tumor cells implantation, avoiding their adhesion and treating the remaining tumor cells with chemotherapy intraperitoneally in a mice model of PM. The bioavailability of the thermogel was tested intraperitoneally in mice. No sign of toxicity was observed in terms of change in body weight, anatomopathology and blood biomarkers. In vitro experiments proved that the thermogel induced limited adhesion of the tumor cells. Loading of oxaliplatin (Ox) and 5-Fluorouracil (5-FU) into the thermogel were able to significantly decreased peritoneal carcinomatosis index (PCI) (-58%) and ascites (-70%) in a murine model of peritoneal metastases. These pre-clinical results confirmed that smart thermogel associated with standard chemotherapy 5-FU and Ox could be a good candidate to decrease the risk of tumor cell implantation during cytoreductive surgery and prevent future metastatic process.

Injured tissues favor cancer cell implantation via fibrin deposits on scar zones

AIM

Evaluation of fibrin role on cancer cells implantation in injured tissues and studying the molecular mechanism of cancer cell interaction with the peritoneal damage.

MATERIAL AND METHODS

Mouse colon cancer (CT26) and human mesothelial cells (HMCs) were used. CT26 cells were implanted on injured peritoneal zones. Icodextrin was used as a lubricant. For in vitro studies, fibrin clots from human plasma were used. The cell-fibrin interaction was observed by optical, electronic, and confocal microscopies. Aprotinin was used as a plasmin inhibitor. Hemostasis impact quantified by (1) the fibrin degradation product D-Dimer and PAR expression in HMCs; (2) the expression of plasminogen activator (PA) and its inhibitor (PAI-1) in cancer cells by qPCR and in supernatants through ELISA after in vitro HMC incubation with 2U of thrombin for 24 h.

RESULTS

(i) Cancer cell lines were adhered and implanted into the wound area in vivo in both the incision and peeling zones of the peritoneum and on the fibrin network in vitro. (ii) Icodextrin significantly inhibited cancer nodule formation in the scar and the incision or peritoneal damaged zones after surgery. (iii) In in vitro studies, cancer cell interaction with the fibrin clot generated a lysed area, causing an increase in plasmin-dependent fibrinolysis measured by D-dimer levels in the supernatants that was inhibited by aprotinin. (iv) Aprotinin inhibited cell-fibrin interaction and invasion. (v) Thrombin upregulates PAI-1 and downregulates PA expression in HMC.

CONCLUSION

Injured tissues favor cancer cell implantation through generated fibrin. Fibrin-cancer cells adhesion can be inhibited by icodextrin.

Predicting Peritoneal Dissemination of Gastric Cancer in the Era of Precision Medicine: Molecular Characterization and Biomarkers

Gastric cancer (GC) is a leading cause of worldwide cancer-related death. Being a highly heterogeneous disease, the current treatment of GC has been suboptimal due to the lack of subtype-dependent therapies. Peritoneal dissemination (PD) is a common pattern of GC metastasis associated with poor prognosis. Therefore, it is urgently necessary to identify patients at high risk of PD. PD is found to be associated with Lauren diffuse type GC. Molecular profiling of GC, especially diffuse type GC, has been utilized to identify molecular alterations and has given rise to various molecular classifications, shedding light on the underlying mechanism of PD and enabling identification of patients at higher PD risk. In addition, a series of diagnositc and prognostic biomarkers of PD from serum, peritoneal lavages and primary GCs have been reported. This comprehensive review summarizes findings on the multi-omic characteristics of diffuse type GC, the clinical significance of updating molecular classifications of GC in association with PD risk and research advances in PD-associated biomarkers.

Free cancer cells in gastric cancer - methods of detection, clinical and prognostic importance (meta-analysis)

Gastric cancer (GC) is one of the most common malignant cancers worldwide. Intraperitoneal dissemination is the typical mechanism of the formation of metastases in GC. The diagnosis of the presence of intraperitoneal free cancer cells (IFCCs) is treated equally to the M (metastasis) category according to the 8^th edition of the TNM classification by the American Joint Committee on Cancer. IFCCs are cells which have detached from the primary tumour through exfoliation into the peritoneal cavity. The source of IFCCs may be iatrogenic due to improper surgical technique during resection of the tumour and may lead to intraperitoneal dissemination. Cytological examination of peritoneal lavage is considered as a gold standard in the confirmation of the presence of IFCCs; however, its sensitivity is very low. In order to increase the sensitivity and reliability of the examination, molecular biology techniques should be applied. In the case of detection of the presence of IFCCs in patients with GC, the patient should be qualified for chemotherapy, or possibly the use of hyperthermic intraperitoneal chemotherapy should be considered.

Pressurized intraperitoneal aerosol chemotherapy and its effect on gastric-cancer-derived peritoneal metastases: an overview

This manuscript aspires to portray a review of the current literature focusing on manifest peritoneal metastasis (PM) derived from gastric cancer and its treatment options. Despite the development of chemotherapy and multimodal treatment options during the last decades, mortality remains high worldwide. After refreshing important epidemiological considerations, the molecular mechanisms currently accepted through which PM occurs are revised. Palliative chemotherapy is the only recommended treatment option for patients with PM of gastric cancer according to the National Comprehensive Cancer Network guidelines, although cytoreductive surgery in combination with hyperthermic intraperitoneal chemotherapy demonstrated promising results in selected patients with regional PM and localized intraabdominal tumor spread. A novel treatment named pressurized intraperitoneal aerosol chemotherapy may have a promising future in improving overall survival with an acceptable postoperative complication rate and stabilizing quality of life during treatment. Additionally, the procedure has been proved to be safe for the patient and medical personnel and a feasible, repeatable method to deter metastatic proliferation. This overview comprehensively addresses this novel and promising treatment in the context of a scientifically and clinically challenging disease.

Use of peritoneal washing cytology for the detection of free peritoneal cancer cells before and after surgical treatment of gastric adenocarcinoma

AIM

Cytological detection of peritoneal-free gastric cancer cells is considered as the gold standard with variable sensitivity. Seeding of cancer cells after radical surgery for gastric cancer is a controversial issue. In this study, it was aimed to detect the rate of positive peritoneal washing cytology and the incidence of spreading of tumor cells after radical surgery.

MATERIALS AND METHODS

Patients with pathologically proven and surgically treated gastric adenocarcinoma were enrolled. Three peritoneal washing samples were examined cytologically: at the beginning, after completion of resection, and before closure of the abdomen. Identification of peritoneal-free gastric cancer cells was regarded as the main outcome.

RESULTS

Thirty-four patients with a mean age of 60.7 ± 12 years were enrolled. T3 and N0 were the most common stages seen in 16 (47%) and 12 patients (35.3%), respectively. There were two positive results (5.9%) as the first peritoneal sample. Considering T3- or N-positive patients, the incidence increased to 9.1%. There was no conversion of negative to positive cytology. Cytological positivity remained only in one case (2.9%) after the second and the third peritoneal samples.

CONCLUSION

Rate of positive peritoneal washing cytology in patients with gastric cancer is influenced by clinicopathological findings and the technique used. Use of cytology alone is thought to be failed to detect free cancers cells within the peritoneal cavity.

Extensive intraperitoneal lavage to eliminate intraperitoneal tumor cells in gastrectomy with D2 lymphadenectomy for gastric cancer

INTRODUCTION:

Survival in gastric cancer is often limited by peritoneal carcinomatosis, which supposedly develops from serosal tumor infiltration or tumor cell spread during gastrectomy with lymphadenectomy. To eliminate peritoneal tumor cells, extensive intraperitoneal lavage (EIPL) has been suggested. Impressive results have been achieved in Japanese trials. In this trial, we assessed EIPL in Western patients.

METHODS:

This prospective trial included patients with non-metastatic gastric adenocarcinoma undergoing gastrectomy with D2 lymphadenectomy. Peritoneal fluid samples at laparotomy, after lymphadenectomy, and after EIPL were analyzed for tumor cells using cytology and EpCAM antibodies. The primary endpoint was peritoneal conversion rate (PCR; proportion of patients in whom EIPL eliminated tumor cells after lymphadenectomy). Secondary endpoints were peritoneal release rate (PRR; proportion of patients with peritoneal tumor cells after gastrectomy/lymphadenectomy among all patients without cells before gastrectomy/lymphadenectomy) and prevalence of peritoneal tumor cells before resection. EIPL was considered ineffective if PCR ⩽ 0.2 and warranted further exploration if PCR ⩾ 0.5. Clinicaltrials.gov identifier is NCT01476553.

RESULTS:

The trial was stopped early because tumor cells after gastrectomy/lymphadenectomy were detected in only 3/27 (11.1%) patients. In none of these did EIPL eliminate tumor cells (PCR 0, 95% confidence interval [CI] 0%-12.5%). In 8/27 (29.6%) patients, tumor cells were detected after EIPL. PRR was 11.1% (95% CI 2.4%-29.2%). There were no perioperative complications higher than Clavien-Dindo grade 3a.

CONCLUSIONS:

In Western patients, free peritoneal tumor cells after gastrectomy with D2 lymphadenectomy for gastric cancer were detected only sporadically. Although based on few cases, the findings suggest that EIPL spreads tumor cells into the peritoneal cavity, thus being potentially harmful. Therefore, EIPL cannot be generally recommended.

Detection of carcinoembryonic antigen in peritoneal fluid of patients undergoing laparoscopic distal gastrectomy with complete mesogastric excision

Background

Surgery for gastric cancer may result in free intraperitoneal cancer cells. This study aimed to determine whether laparoscopic gastrectomy with complete mesogastric excision (D2 + CME) reduces the number of free intraperitoneal cancer cells.

Methods

Patients with gastric cancer who had a conventional D2 or D2 + CME laparoscopic distal gastrectomy between April 2015 and February 2017 were included in the study. Intraoperative peritoneal washings were collected before and after tumour resection. Reverse transcriptase–quantitative real-time PCR for carcinoembryonic antigen (CEA) was used to assess the presence of gastric cancer cells.

Results

Eighty-five patients underwent conventional D2 lymphadenectomy and 76 had the D2 + CME procedure. Of 161 peritoneal fluid samples obtained before gastrectomy, 137 (D2, 72; D2 + CME, 65) had low CEA expression indicative of no cancer cells. After gastrectomy, high CEA expression was detected in 23 of the 72 samples (32 per cent) from patients in the D2 group, and in ten of the 65 samples (15 per cent) from the D2 + CME group. In the overall cohort, mean CEA expression level after gastrectomy was lower in the D2 + CME group than in the D2 group (P = 0·0038). In patients with low CEA expression before gastrectomy, disease-free survival in the D2 + CME group was better than that in the D2 group (P = 0·033).

Conclusion

Laparoscopic distal gastrectomy with complete mesogastric excision reduces the number of free intraperitoneal cancer cells and is associated with a better disease-free survival than conventional D2 gastrectomy.

Risk of peritoneal metastases in patients who had negative peritoneal staging and received therapy for localized gastric adenocarcinoma

BACKGROUND

Positive peritoneal cytology (+PCyt) or gross carcinomatosis (GPC) carries a poor prognosis. Laparoscopic staging to detect +PCyt/GPC is recommended for all ≥T1b gastric adenocarcinoma (GAC). The natural history of patients with GAC who have baseline -PCyt and then undergo multimodality therapy is not well documented, particularly for the risk of subsequent GPC.

METHODS

We identified 238 GAC patients with baseline -PCyt who were followed for the development of peritoneal carcinomatosis (PC). Standard statistical methods were employed.

RESULTS

Of 238 patients, 192 had attempted surgery after preoperative therapy. Of these, 13 patients (6.8%) had GPC and one had liver metastases, thus surgery was aborted. We followed 164 patients who had an R0 resection. The median follow-up duration was 3.4 (range, 0.6-18) years. The rate of PC was 13.4%, (22/164 patients) and the median time to PC was 15.6 months. Female gender was associated with PC on multivariate analysis. The 5-year OS rate for patients without subsequent PC was 75%. Conclusion Even with baseline -Cyt, ∼25% of patients develop PC following multimodality therapy. Patients who do not develop PC have an excellent OS rate. Further research is warranted to detect PC at baseline by the use of biomarkers.

Mechanisms of peritoneal dissemination in gastric cancer

Peritoneal dissemination is the most frequent metastatic pattern of gastric cancer, but the mechanisms underlying peritoneal dissemination are yet to be elucidated. Paget's 'seed and soil' hypothesis is recognized as the fundamental theory of metastasis. The 'seeding' theory proposes that the formation of peritoneal dissemination is a multistep process, including detachment from the primary tumour, transmigration and attachment to the distant peritoneum, invasion into subperitoneal tissue and proliferation with blood vascular neogenesis. In the present review, the progress of each step is discussed. Milky spots, as a lymphatic apparatus, are indicative of lymphatic orifices on the surface of the peritoneum. These stomata are open gates for peritoneal-free cancer cells to migrate into the submesothelial space. Therefore, milky spots provide suitable 'soil' for cancer cells to implant. Other theories have also been proposed to clarify the peritoneal dissemination process, including the transvessel metastasis theory, which suggests that the peritoneal metastasis of gastric cancer develops via a vascular network mediated by hypoxia inducible factor-1α.

Blockade of potassium ion transports enhances hypotonicity-induced cytocidal effects in gastric cancer

Background

Peritoneal lavage with distilled water has been used for surgeries of various cancers to reduce peritoneal recurrence. This study examined whether blockade of potassium ion transports enhances hypotonicity-induced cytocidal effects in gastric cancer (GC).

Results

A potassium channel blocker inhibited the occurrence of regulatory volume decrease (RVD) induced by mild hypotonic stimulation, and significantly enhanced cytocidal effects on GC cells. Incubating MKN45 cells with hypotonic solutions containing a potassium channel blocker significantly reduced the formation of peritoneal metastases in nude mice.

Methods

The three human GC cell lines (HGC-27, Kato III, and MKN45) were exposed to mild hypotonic solutions, and the effects of blockade of potassium ion transports during hypotonic stimulation on cell volume changes and cell viabilities were examined. In the in vivo study, MKN45 cells stimulated with mild hypotonic solutions were intraperitoneally injected into nude mice, and the effects of blockade of potassium ion transports during hypotonic stimulation on the formation of peritoneal metastases were evaluated.

Conclusions

Blockade of potassium ion transports enhances hypotonicity-induced cytocidal effects on GC cells, which may contribute to development of a novel lavage method for further reduction of peritoneal recurrence in GC.

Is noncurative gastrectomy always a beneficial strategy for stage IV gastric cancer?

Purpose

The purpose of this study is to suggest a treatment strategy for stage IV gastric cancer by investigating the behavioral difference between initially and recurrent metastatic disease.

Methods

We reviewed the medical records of the patients who underwent chemotherapy alone for metastatic gastric cancer between January 2006 and September 2013. Patients were divided into those who underwent chemotherapy for metastatic disease since initial diagnosis (IM group) and for metastatic recurrence after curative surgery (RM group). Survival and causes of death were compared between the 2 groups, and significant prognostic factors were also investigated.

Results

A total of 170 patients were enrolled in this study. Of these patients, 104 were included in the IM group and 66 in the RM group. Overall survival of the IM group did not differ from that of RM (P = 0.569). In the comparison of the causes of death, the IM group had a greater tendency to die from bleeding (P = 0.054) and pneumonia (P = 0.055). In multivariate analysis, bone metastasis (P < 0.001; HR = 2.847), carcinoma peritonei (P = 0.047; HR = 1.766), and the frequency of chemotherapy (P < 0.001; HR = 0.777) were significantly associated with overall survival of IM group.

Conclusion

Disease-burden mainly contributes to the prognosis of metastatic gastric cancer, although noncurative gastrectomy may be helpful in reducing the mortality of initially metastatic disease. Therefore, disease-burden should be also prioritized in determining the treatment strategies for stage IV gastric cancer.

Prognostic impact of CD44-positive cancer stem-like cells at the invasive front of gastric cancer

Background:

The invasive tumour front may provide prognostic information. We examined the relationship between the presence of cancer stem cells (CSCs) at the invasive tumour front and prognosis in gastric cancer (GC).

Methods:

CD44 is a CSC marker; accordingly, CD44 standard (CD44s), CD44 variant-6 (CD44v6), and CD44 variant-9 (CD44v9) expression were examined in 123 resected primary GCs and the clinical significance of CSCs at the invasive tumour front was analysed.

Results:

Thirteen (10.6%), 79 (64.2%), and 47 (38.2%) GCs were CD44s-, CD44v6-, and CD44v9-positive, respectively. Patients with CD44-positive expression at the invasive tumour front had significantly poorer disease-specific survival than those with negative expression (CD44s: P<0.00001, CD44v6: P=0.013, CD44v9: P=0.0002). CD44s expression at the invasive tumour front was an independent prognostic factor in resectable GC patients (hazard ratio=3.13; 95% confidence interval, 1.09–9.01; P=0.035) and was significantly associated with peritoneal (P<0.001), lymphatic (P<0.001), and haematogenous recurrences (P=0.008). In addition, the number of CD44 isoforms expressed in cancer cells at the invasive tumour front was associated with patient prognosis. No conventional clinicopathological factors were independently associated with CD44 expression at the invasive tumour front.

Conclusions:

CD44-positive cancer stem-like cells at the invasive tumour front indicate poor survival and can be a unique biological prognostic factor for GC.

Recursive partition analysis of peritoneal and systemic recurrence in patients with gastric cancer who underwent D2 gastrectomy: Implications for neoadjuvant therapy consideration

BACKGROUND AND OBJECTIVES

To classify patients with nonmetastatic advanced gastric cancer who underwent D2-gastrectomy into prognostic groups based on peritoneal and systemic recurrence risks.

METHODS

Between 2004 and 2007, 1,090 patients with T3-4 or N+ gastric cancer were identified from our registry. Recurrence rates were estimated using a competing-risk analysis. Different prognostic groups were defined using recursive partitioning analysis (RPA).

RESULTS

Median follow-up was 7 years. In the RPA-model for peritoneal recurrence risk, the initial node was split by T stage, indicating that differences between patients with T1-3 and T4 cancer were the greatest. The 5-year peritoneal recurrence rates for patients with T4 (n = 627) and T1-3 (n = 463) disease were 34.3% and 9.1%, respectively. N stage and neural invasion had an additive impact on high-risk patients. The RPA model for systemic relapse incorporated N stage alone and gave two terminal nodes: N0-2 (n = 721) and N3 (n = 369). The 5-year cumulative incidences were 7.7% and 24.5%, respectively.

CONCLUSIONS

We proposed risk stratification models of peritoneal and systemic recurrence in patients undergoing D2-gastrectomy. This classification could be used for stratification protocols in future studies evaluating adjuvant therapies such as preoperative chemoradiotherapy. J. Surg. Oncol. 2016;114:859-864. © 2016 2016 Wiley Periodicals, Inc.

Pyomyositis at the surgical site in a patient with chronic myeloid leukemia: a case report and literature review

BACKGROUND

Pyomyositis is a rare, subacute, deep pyogenic infection of the muscle tissue. This disease has been previously described in patients that were immunocompromised due to a hematological malignancy.

CASE PRESENTATION

A 68-year-old man with a history of chronic myeloid leukemia was treated with imatinib. He was diagnosed with ascending colon cancer and underwent curative surgery. His postoperative course was uneventful, and he was healthy at 6 months after surgery, allowing for reinitiation of imatinib therapy. After the reinitiation of therapy, a computed tomography (CT) scan revealed a mass shadow in the right iliopsoas muscle. This lesion was clinically diagnosed as recurrent colon cancer with an abscess, which was resected surgically. A pathological examination uncovered both edema and inflammation. Two months after the second surgery, imatinib therapy was reinitiated; however, he again developed painful swelling and erythema in his right thigh. A CT scan revealed a similar shadow as described previously. He was then diagnosed with pyomyositis; he underwent incisional drainage and was administered linezolid. Following the treatment for pyomyositis, there was no cancer recurrence or evidence of any recurrent pyomyositis.

CONCLUSIONS

Findings from this case suggest that both undergoing surgery and receiving imatinib therapy may modulate an individual's immune response, whereby the surgical site becomes more prone to infection and may predispose an individual to pyomyositis. The case report is followed by a discussion of the literature regarding this disease, including potential risk factors and the underlying pathogenesis.

Adhesion molecules in peritoneal dissemination: function, prognostic relevance and therapeutic options

Peritoneal dissemination is diagnosed in 10–25 % of colorectal cancer patients. Selected patients are treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy. For these patients, earlier diagnosis, optimised selection criteria and a personalised approach are warranted. Biomarkers could play a crucial role here. However, little is known about possible candidates. Considering tumour cell adhesion as a key step in peritoneal dissemination, we aim to provide an overview of the functional importance of adhesion molecules in peritoneal dissemination and discuss the prognostic, diagnostic and therapeutic options of these candidate biomarkers. A systematic literature search was conducted according to the PRISMA guidelines. In 132 in vitro, ex vivo and in vivo studies published between 1995 and 2013, we identified twelve possibly relevant adhesion molecules in various cancers that disseminate peritoneally. The most studied molecules in tumour cell adhesion are integrin α2β1, CD44 s and MUC16. Furthermore, L1CAM, EpCAM, MUC1, sLe^x and Le^x, chemokine receptors, Betaig-H3 and uPAR might be of clinical importance. ICAM1 was found to be less relevant in tumour cell adhesion in the context of peritoneal metastases. Based on currently available data, sLe^a and MUC16 are the most promising prognostic biomarkers for colorectal peritoneal metastases that may help improve patient selection. Different adhesion molecules appear expressed in haematogenous and transcoelomic spread, indicating two different attachment processes. However, our extensive assessment of available literature reveals that knowledge on metastasis-specific genes and their possible candidates is far from complete.

Prognostic Significance of Molecular Analysis of Peritoneal Fluid for Patients with Gastric Cancer: A Meta-Analysis

Background

Accurately distinguishing serosal invasion in patients with gastric cancer (GC) prior to surgery can be difficult. Molecular analysis of peritoneal fluid (MAPF) for free cancer cells with higher sensitivity than other methods; however, its prognostic value for GC remains controversial, precluding its application in clinical practice.

Methods

PubMed, EMBASE and other databases were systematically searched. Thirty-one studies were eligible for the meta-analysis. Hazard ratios (HRs) and 95% confidence intervals (CIs) were pooled for overall survival (OS), disease-free survival (DFS) and peritoneal recurrence-free survival (PRF).

Results

The current meta-analysis focused on patients with GC and negative cytological diagnoses. The results showed that positive MAPF status (MAPF⁺) led to poorer prognoses for OS (HR 2.59, 95% CI 1.99–3.37), DFS (HR 4.92, 95% CI 3.28–7.37) and PRF (HR 2.81, 95% CI 2.12–3.72) compared with negative MAPF status (MAPF^-). Moreover, among the patients with GC who received curative treatment, the MAPF⁺ patients had poorer prognoses for OS (HR 3.27, 95% CI 2.49–4.29), DFS (HR 3.90, 95% CI 2.74–5.57) and PRF (HR 5.45, 95% CI 3.70–8.03). A meta-analysis of multivariate-adjusted HRs demonstrated that MAPF⁺ status was an independent prognostic factor for patients with GC who underwent curative treatment (OS: HR 2.19, 95% CI 1.47–3.28; PRF: HR 3.44, 95% CI 2.01–5.87). Using the identical target genes (CEA, CEA/CK20) as molecular markers, the patients with GC who were MAPF⁺ had significantly worse prognoses for OS (CEA: HR 3.03, 95% CI 2.29–4.01; CEA/CK20: HR 4.24, 95% CI 2.42–7.40), DFS (CEA: HR 3.99, 95% CI 2.24–7.12; CEA/CK20: HR 4.31, 95% CI 1.49–2.48) and PRF (CEA: HR 4.45, 95% CI 2.72–7.31; CEA/CK20: HR 6.46, 95% CI 3.62–11.55) than the patients who were MAPF^-.

Conclusion/Significance

The above results demonstrate that MAPF could be a prognostic indicator for patients with GC who have a negative cytological diagnosis and/or are receiving curative treatment. MAPF could provide clinicians with additional prognostic information that could aid in developing individualized treatment plans prior to surgery. The widely used target genes CEA, CEA/CK20 were confirmed to be valuable MAPF markers for predicting the prognosis of GC.

Free intraperitoneal tumor cells and outcome in gastric cancer patients: a systematic review and meta-analysis

PURPOSE

Despite continuously improving therapies, gastric cancer still shows poor survival in locally advanced stages with local recurrence rates of up to 50% and peritoneal recurrence rates of 17% after curative surgery. We performed a systematic review with meta-analyses to clarify whether positive intraperitoneal cytology (IPC) indicates a high risk of disease recurrence and poor overall survival in gastric cancer.

METHODS

Multiple databases were searched in December 2014 to identify studies on the prognostic significance of positive intraperitoneal cytology in gastric cancer, including: Medline, Biosis, Science Citation Index, Embase, CCMed and publisher databases. Hazard ratios (HR) and associated 95% confidence intervals (CI) were extracted from the identified studies. A meta-analysis was performed using a random-effects model on overall survival, disease-free survival and peritoneal recurrence free survival.

RESULTS

A total of 64 studies with a cumulative sample size of 12,883 patients were included. Cytology, quantitative real time polymerase chain reaction (PCR) or both were performed in 35; 21 and 8 studies, respectively. Meta analyses revealed free intraperitoneal tumor cells (FITC) to be associated with poor overall survival in univariate (HR 3.27; 95% CI 2.82 - 3.78]) and multivariate (HR 2.45; 95% CI 2.04 - 2.94) analysis and poor peritoneal recurrence free survival in univariate (4.15; 95% CI 3.10 - 5.57) and multivariate (3.09; 95% CI 2.02 - 4.71) analysis. Subgroup analysis showed this effect to be independent of the detection method, Western or Asian origin or the time of publication.

CONCLUSIONS

FITC oder positive peritoneal cytology is associated with poor survival and increased peritoneal recurrence in gastric cancer.

Clinical importance of a transcription reverse-transcription concerted (TRC) diagnosis using peritoneal lavage fluids obtained pre- and post-lymphadenectomy from gastric cancer patients

PURPOSE

Our previous study demonstrated that a transcription reverse-transcription concerted (TRC) diagnosis using peritoneal lavage fluids at laparotomy was a potential prognostic factor for gastric cancer patients; however, the clinical importance of a TRC diagnosis from peritoneal lavage fluids after lymphadenectomy remains unclear.

METHODS

TRC amplification targeting CEA mRNA was utilized to detect free cancer cells before and after lymphadenectomy during gastric cancer resection. Of 120 patients who underwent curative gastrectomy for cT2-T4 gastric cancer, 38 whose peritoneal lavage samples were collected pre- and post-lymphadenectomy were eligible for analysis.

RESULTS

Six (16.0 %) patients had CEA positivity before lymphadenectomy (pre-CEA), whereas nine (23.7 %) had CEA positivity after lymphadenectomy (post-CEA). Post-CEA was significantly correlated with higher pathological N-stage. Moreover, the positive post-CEA group had significantly worse relapse-free survival than the negative post-CEA group (p = 0.001). Cox multivariate analysis revealed that post-CEA positivity was a significant predictor of poor relapse-free survival (p = 0.012). It was also a predictor of distant metastasis, but not specific for peritoneal recurrence.

CONCLUSIONS

These findings demonstrated that post-CEA positivity in a TRC diagnosis was a potential predictor of disease recurrence, but not a specific predictor of peritoneal recurrence.

Long-term outcomes after prophylactic bursectomy in patients with resectable gastric cancer: Final analysis of a multicenter randomized controlled trial

BACKGROUND

Bursectomy, a traditional operative procedure to remove the peritoneal lining covering the pancreas and the anterior plane of the transverse mesocolon, has been performed for serosa-positive gastric cancer in Japan and Eastern Asia. We conducted a multicenter, randomized, controlled trial to demonstrate the noninferiority of the omission of bursectomy.

METHODS

Between July 2002 and January 2007, 210 patients with cT2-3 gastric adenocarcinoma were randomized intraoperatively to D2 gastrectomy with or without bursectomy. The primary endpoint was overall survival (OS). We provide the results of the final analysis of the complete 5-year follow-up data.

RESULTS

After the median follow-up of 80 months, 5-year OS was 77.5% for the bursectomy group and 71.3% for the nonbursectomy group (2-sided P = .16 for superiority; 1-sided P = .99 for noninferiority). The hazard ratio for death in the nonbursectomy group was 1.40 (95% CI, 0.87-2.25). The 5-year recurrence-free survivals were 73.7% and 66.6% in the bursectomy and nonbursectomy groups, respectively (2-sided P = .33 for superiority; 1-sided P = .99 for noninferiority). Cox multivariate analysis revealed that bursectomy was an independent prognostic factor of good OS (P = .033). Subgroup analysis showed a trend toward improved survival after bursectomy for tumors in the middle or lower third of the stomach and for pathologically serosa-positive tumors.

CONCLUSION

The final analysis could not demonstrate the noninferiority of the omission of bursectomy. Bursectomy should not be abandoned as a futile procedure.

Successful surgical approach for a patient with encapsulating peritoneal sclerosis after hyperthermic intraperitoneal chemotherapy: a case report and literature review

Background

Encapsulating peritoneal sclerosis (EPS) is a rare surgical complication that can occur after intraperitoneal treatment. It is also a serious and potentially fatal complication of continuous ambulatory peritoneal dialysis. The present report describes a case of surgically treated EPS that probably occurred as a complication of hyperthermic intraperitonal chemotherapy (HIPEC).

Case presentation

A 39-year-old man required sigmoidectomy for serosal invasive advanced sigmoid colon cancer. HIPEC with oxaliplatin, 5-fluorouracil and mitomycin C were given as adjuvant therapy. Subsequently, intestinal obstruction developed at 15 months postoperatively, and the patient was hospitalized. Abdominal computed tomography showed a dilated small intestine enveloped by a thickened membrane. We found no evidence of peritoneal recurrence, but exploratory surgery revealed EPS, probably caused by HIPEC. We peeled the capsule off of the intestine. The patient’s postoperative course was uneventful, and sufficient nutritional intake after surgery was noted. Seven months after surgery, he is well with no recurrence.

Conclusion

The surgical treatment via peritonectomy and enterolysis for postoperative EPS appears safe and effective. A diagnosis of EPS should be considered when intestinal obstruction does not show improvement with conservative treatment in patients who have undergone HIPEC, provided the possibility of peritoneal cancer recurrence is excluded.